Malosma Laurina (Nutt.) Abrams, LAUREL SUMAC. Large Shrub
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Malosma laurina (Nutt.) Abrams, LAUREL SUMAC. Large shrub, evergreen, with a dense canopy, 200−600 cm tall; ± dioecious; shoots glabrous, strongly aromatic when cut or crushed (having resin ducts with terpenes). Stems: cylindric, maroon-red when young or turning red on exposed surfaces, often glaucous; older stems smooth, reddish brown; bark dull light gray. Leaves: helically alternate, simple, petiolate, without stipules; petiole often ridged on sides and with raised midvein, 10–40 mm long, often maroon-red; blade elliptic or lanceolate to oblong, 30–190 × 15–85 mm, ± leathery, folded upward from midrib, broadly tapered to weakly cordate at base, entire, acute to obtuse with short point at tip, pinnately veined with midrib raised on both surfaces, glossy and maroon-red when first expanding maturing dull green due to surface wax, the margins narrowly translucent when young aging reddish and opaque. Inflorescences: dense panicles, terminal, with unisexual flowers either staminate (staminate plants) or pistillate with or without some staminate flowers (pistillate plants), panicle conic, ovoid, or ellipsoid, 45−220 mm long, with 3−4 orders of branching, many-flowered, flowers on short branches with 1−4 flowers opening in descending order, bracteate, glabrous; bract subtending peduncle and lower lateral branches leaflike, persistent, bract subtending lateral branch or branchlet often present, awl-shaped; bractlet subtending pedicel awl-shaped, 0.5−1.5 mm long; pedicel ca. 0.5 mm long. Staminate flower: radial, 3−4 mm across; sepals 5, deltate, 0.7–1 × 0.7– 1.3 mm, green sometimes with reddish glandular dots, white-membranous on margins, acute to obtuse at tip; petals 5, spreading but becoming recurved, somewhat overlapping, oblong to elliptic, 1.6−2.4 × 1−1.3 mm, white; stamens 5, free, opposite sepals; filaments erect, narrowly triangular, 1−1.7 mm long, white becoming pale lavender above midpoint; anthers ± versatile, dithecal, 1−1.3 mm long, yellow (fading after dehiscence), longitudinally dehiscent; pollen yellow; nectary disc surrounding ovary inside filaments, ringlike, 1−1.2 mm across, disc ca. 0.4 wide, weakly 5-lobed, yellowish green aging yellowish pink to reddish orange, with copious nectar; pistil 1, 0.8−1 mm long, pinkish with rose at tips, sterile; ovary superior, ca. 0.4 mm long; styles 3, equal to unequal. Pistillate flower: radial, 2.2−3 mm across; sepals 5, deltate, 0.7–1 × 0.7–1.3 mm, green to rose, white-membranous on margins, acute to obtuse at tip; petals 5, spreading becoming recurved, somewhat overlapping, oblong to elliptic, 1.3–2 × 0.6–1 mm, white (an individual rarely pinkish to rose-red); stamens 5, free, sterile; filaments 0.6−0.8 mm long, white; anthers dorsifixed, dithecal, ca. 0.5 mm long, pale yellow; nectary disc surrounding ovary inside filaments, ringlike, 1−1.2 mm across, disc ca. 0.4 wide, weakly 5-lobed, yellowish green aging yellowish pink to reddish orange, with copious nectar; pistil 1, 0.9– 1.1 mm long; ovary superior, spheroid, 0.6–0.7 mm, often rose-colored at top and the base of styles, 1-chambered with 1 ovule; styles 3(−4), ± 0.5 mm long, very pale yellowish green, stigmatic at tip; stigmas yellowish pink or pale greenish with pinkish margin aging deep purple. Fruit: drupelike, with 1 stone, spheric to somewhat compressed and typically ridged along 1 edge, 2.5–3 mm, initially deep red-purple aging white, glabrous; pulp thin, fleshy, resinous; stone broadly kidney-shaped, 2 mm long, brownish olive green. Early June−mid-August. Native. An aromatic, evergreen shrub found throughout the range from coastal bluff along the coast (away from salt spray) to typical coastal sage scrub and chaparral communities. Malosma laurina resprouts vigorously after fires by producing deep maroon-red shoots from the plant base. Wherever a slope covered with chaparral is relatively low in stature, Malosma laurina often is the emergent life form that dots the hillside. This species flowers during early summer, when its inflorescences become covered with bees. Laurel sumac is dioecious, basically having staminate and pistillate plants, and, of course, only the pistillate individuals produce the drupelike fruits, dispersed by birds. Both flower types have nectaries and all floral parts, but the staminate flower forms an abortive pistillate, and pistillate flowers typically have smaller anthers that are sterile. In range, in about five percent of a population one can find staminate flowers on an otherwise pistillate plant. B. A. Prigge & A. C. Gibson .